Simulation of turbo codes in digital communication

The basic aim of communication systems is to develop technologies and algorithms, whose cost is low and efficiency is high as much as possible.Therefore, it is necessary to encode the message packages in the best manner, to be affected from the noise at a minimum level during the transmission and to ensure that the message package is received by the receiver with a minimum level of error.A wide-variety of algorithms have been developed since the 1950?s and during that period Shannon limits have determined theoretically the highest efficiency that can be obtained in a communication system. Turbo Code algorithm has been the most successful one and provided the highest encoding gain in theory among these algorithms.In the first part of the thesis, encoding gain and Shannon limits that will be deemed as a reference for communication systems are mentioned. Later in the thesis, an introduction is made to Turbo Encoding and how the encoding is performed is examined in detail. In the next part details regarding the decoding of the encoded message have been presented. The BCJR algorithm among the important algorithms used for the decoding of the encoded message has been examined.In the final part, a simulation written with C++ regarding encoding and decoding is presented.